Current and Prior Chemistry Research Experience
220 South Linden Ave., Suite L
South San Francisco, CA 94080
As a member of the Stacy Group in the Department of Chemistry here at UC Berkeley, I've been working jointly with Professor George Brimhall in the Geology Department to better understand a new Chilean copper ore. Unlike most copper sulfide-based copper ores, this is an oxide-based ore with fascinating environmental and chemical implications as refinement of these ores provides us with an environmentally-friendly route to copper metal. There are several geochemistry questions this ores poses us with. I am currently exploring a variety of routes to prepare this K/Mn/Cu/Co/O ore including hydrothermal, flux and solid state-based routes. Concurrently I am exploring a variety of analytical fingerprint techniques to yield a positive identification match for the materials synthesized. Although I have focused primarily on Cu, Fe and Mo powder X-ray diffraction techniques I am currently investigating electron diffraction as a shorter range diffraction tool. Once these materials can be prepared free of their geologic impurities their thermodynamic properties can be explored to help better model their geologic past.
Prior to the copper ore project I was working to better understand the use of molten nitrate and hydroxide fluxes in the synthesis of mixed valent metal oxides, namely superconductors including La2-xNaxCuO4, La2-xKxCuO4, La2-xSrxCuO4, Ba1-xKxBiO3, Sr2CuO3+x, and Ca2CuO3+x .
Here are some of the pieces of equipment I've set up and use all the time.
And sometimes reactions don't go as planned with the equipment and an explosion ensues...
Prior to coming to UC Berkeley, I attended UC Santa Barbara where I received my Bachelors of Science degree in Chemistry in 1992. For the four years while I attending UCSB, I worked under the direction of Professor Galen Stucky in the Department of Chemistry. As a member of the Stucky Group, I worked on the synthesis of several solid state oxide materials by classical solid state, gel, non-aqueous flux, and hydrothermal synthetic techniques. My research began with the study of several Nonlinear Optical (NLO) Materials including KTiOPO4 (KTP) and several of it's isostructural analogs including NaTiOPO4, KVOPO4, KTiOAsO4, and AgTiOPO4. With partial funding from the President's Undergraduate Fellowship, 1990-1991, I worked on the synthesis of a new class of open framework molecular sieves, CsZnPO4, with potential applications in chiral separations and catalysis. After mapping out the Cs/Zn/P/O ternary phase space, I moved on to work with a few catalytically relevant aluminophosphate molecular sieve materials including AlPO4-5, AlPO4-11 and VPI-5. In my last year at UCSB with partial funding from the President's Undergraduate Fellowship, 1991-1992, I prepared a new NLO material with an all-trans titanyl chain unlike the cis-trans titanyl chain found in KTP. The second harmonic generation (SHG) of this material is quite impressive and single crystal structures of this material and several of its precursors have been solved by single crystal X-ray diffraction. They reveal a fascinating molecular building block synthesis from isolated molecules to acentric titanyl chains. Hopefully we'll finish writing up the paper in '96.
During the summer of 1991 I worked under the direction of Professor Walter Klemperer at the Beckman Institute at the University of Illinois, Urbana-Champaign as a NSF Solid State Inorganic Chemistry Summer Fellow. While at UIUC I investigated the growth of microporous aluminophosphate molecular sieves (ALPO) including AlPO4-5, AlPO4-8, AlPO4-11, AlPO4-12, and VPI-5 to determine their suitability for seeded hydrothermal crystal growth. Reaction conditions were varied to observe their influence on the phase, size, and quality of the crystals obtained.
During the summers and vacations between 1988 and 1992 I worked under the direction of Professor M. Frederick Hawthorne in the Department of Chemistry and Biochemistry at the University of California, Los Angeles on boron chemistry. My UCLA research began with the synthesis and purification of a variety of substituted organoboranes. I later worked on a Boron Neutron Capture Therapy of cancer project (BNCT) in conjunction with the City of Hope National Medical Center in Duarte, California. This project began with the solid phase Merrifield peptide synthesis of several tetradecapeptide manifolds equipped with the proper functional groups for later conjugation with 10B-enriched carborane-containing peptides. This boron containing manifold was to be linked with a tumor directing antibody, and attached in vivo to cancerous tumors. A mild neutron flux would then destroy the cancerous tumor cells.
In the process of my studies I have utilized a number of synthetic techniques including inert atmosphere and high vacuum environments, extractions, sublimations, distillations, crystallizations, chromatography, including column and HPLC, Schlenk line, seeded growth, ion exchange, gel, hydrothermal, nonaqueous flux (phosphate, chloride, fluoride, sulfate, sulfite, nitrite, nitrate, hydroxide, oxide), and classical solid state techniques, and have had the opportunity to use a variety of instruments including powder X-ray diffractometers (Siemens D5000, Scintag, Rigaku), single crystal X-ray diffractometers (Siemens SMART, Huber, Enraf Nonius CAD4), thermogravimetric analyzer (TGA) (DuPont, Shimadzu), differential thermal analyzer (DTA), differential scanning calorimeter (DSC), solid phase Merrifield peptide synthesizer, 1H NMR, 13C NMR, 11B NMR, Fourier Transform IR Spectrometer, UV-Vis Spectrometer, FAB Mass Spectrometer, Atomic Absorption Spectrometer, Nd:YAG laser (Spectra Physics), potentiostat, galvanostat, and a SQUID Magnetometer (Quantum Design).